using System.Linq;

namespace FindtheDifference
{
    public class Solution
    {
        public char FindTheDifference(string s, string t)
        {
            foreach (var c in s)
            {
                int index = t.IndexOf(c);
                if (index == -1)
                {
                    return '\0';
                }
                t = t.Remove(index, 1);
            }
            
            return t[0];
        }
    }
}